//C05:wheat.c -- exp
#include <stdio.h>
#define SQUARES 64
#define CROP 1E15
int main(void)
{
    double current, total;
    int count = 1;
    printf("square grains total ");
    printf("fraction of \n");
    printf("    added   grain   ");
    printf("US total\n");
    total = current = 1.0;
    printf("%4d %13.2e %12.2e %12.2e", count, current,
        total, total/CROP);
    while(count < SQUARES)
    {
        count = count + 1;
        current = 2.0 * current;
        total = total + current;
        printf("%4d %13.2e %12.2e %12.2e", count, current,
        total, total/CROP);
    }    
    printf("That's all.\n");
}